Currently, with rapid expansion of the Internet in scale, an existing routing system is excessively unwieldy and has relatively poor controllability. Therefore, a new network architecture idea is required to maintain sustainable development of the Internet. In view of this, the OpenFlow technology emerges accordingly. The OpenFlow technology is a set of exchange standards supporting an open interface and multi-layer control. In the OpenFlow technology, based on an existing Transmission Control Protocol/Internet Protocol (TCP/IP) technology, a data packet forwarding process that is originally controlled by a traditional switch/router is transformed into independent processes that are separately completed by an OpenFlow switch (referred to as a switch) and an OpenFlow controller (referred to as a controller) that support the OpenFlow technology, which implements separation of a forwarding plane and a control plane.
Currently, it has become a trend to apply the OpenFlow technology to a mobile core network. However, after the OpenFlow technology is applied to the mobile core network, a packet transmission may fail when a packet is transmitted from the mobile core network to an external network.